--- Have you solved your problem?---I've kept on thinking about that matter ______, but I have no idea yet now.
---What’s wrong ______ Maria? ---She has a cold. A. with B. of C. about
—Sorry, I made a mistake again. —________. Practice more and you will succeed.
—Thanks for listening to my problem and ______ me your valuable advice.—__________.
The fat boy always worries about _______ enough food _______ every day. How funny!
Why not ______ your teacher for advice when you don’t know ______ the problems?